1. Field of the Invention
The present invention relates generally to digital data transmission and, specifically, to a method and apparatus for correcting errors in digital audio signals.
2. Description of the Prior Art
It is known to use the so-called cross-interleave technique to provide a correctable error code for digital data transmission. This technique involves delaying the various words making up the digital data series by different predetermined amounts, thereby time interleaving the data, and then transmitting the time interleaved data. The interleaved data is received and each word appropriately delayed by different corresponding times in an inverse pattern, based upon the original delays to reconstitute or reassemble the digital data in its original form.
It is the usual practice when using the cross-interleave technique to use modulo 2 adders to generate two parity series, each representing the data words in two different arrangements. Because each word of the digital data signal will be contained in these two parity series, it can be seen that this known cross-interleave technique provides an error correcting capability that is quite high. Nevertheless, when multiple words containing errors are transmitted, the cross-interleave technique is not sufficiently powerful and the errors cannot be corrected.